1. Field of the Invention
The present invention relates to a vehicle lamp equipped with an LED (light-emitting diode). More particularly, the invention relates to a vehicle lamp equipped with an LED including a normal reflection section and an internal reflection section which, when used in conjunction with a plurality of reflection elements having multiple configuration placements, are operable to control reflection and the outgoing light.
2. Description of the Related Art
Many vehicle lamps equipped with an LED have been recently adopted. In this regard, JP-UM-A-61-153201 describes a vehicle lamp equipped with an LED light source oriented forward of the vehicle lamp. Further, a translucent member is arranged such that light originating from the LED light source is caused to enter the translucent member. The light that has originated from the LED light source and entered the translucent member is reflected rearward by a front surface of the translucent member. The thus-reflected rearward light is then reflected forward by a rear surface, whereupon the light exits forward of the lamp from the translucent member.
Such a vehicle lamp can reflect backward, by means of internal reflection, light which enters the translucent member at a large angle with respect to an optical axis of the LED light source from among the light which has originated from the LED light source and entered the front surface of the translucent member. However, the light that enters the translucent member at a small angle with respect to the optical axis assumes an incident angle which is smaller than or equal to a critical angle. Hence, the light cannot be reflected rearward through internal reflection.
As described in the Japanese Patent Publication, if an area on the front surface of the translucent member located in the vicinity of the optical axis is formed into a recessed section of a wedge-shaped cross-sectional profile, the light originating from the LED light source can be caused to enter the wedge-shaped recessed section at an angle exceeding the critical angle. As a result, the light originating from the LED light source can be utilized efficiently as lamp illumination light.
However, when such a lamp structure is adopted, an overlap exists between an area on the rear surface of the translucent member, where the light that has been subjected to internal reflection on the wedge-shaped recessed section (i.e., wedged-recess-reflected light) enters, and an area on the front surface of the translucent member where the light that has been subjected to internal reflection on areas other than the wedge-shaped recessed section (i.e., general-section-reflected light) enters. If the geometry of the rear surface of the translucent member is set so as to enable appropriate control of reflection of the general-section-reflected light, there arises a problem of inability to appropriately control reflection of the wedged-recess-reflected light.
The invention has been conceived to overcome these problems with the related art and is aimed at providing a vehicle lamp which is equipped with an LED light source and enables efficient utilization the light originating from the LED light source as lamp illumination light and appropriate control of the lamp illumination light.